Determine the Vmax and the Km of the enzyme in the absence and presence of each inhibitor. Calculate the KI for each inhibitor. Are the inhibitors all the same? Which is the best inhibitor and why? What is the catalytic efficiency and turnover number of the enzyme knowing that during the experiments its concentration was 2 nM? What happens to the catalytic efficiency and turnover number of the enzyme in the presence of each of the inhibitor?

The following velocity data were obtained for an enzymatic reaction in the absence and presence of three different inhibitors (A, B, and C):

Initial velocity (v) Initial velocity (v) Initial velocity (v) Initial Velocity (v)

[S] Control (no inhibitor) (+A at 6μM) (+B at 30μM) (+C at 4mM)

(mM) (nM/min) (nM/min) (nM/min) (nM/min)

0.200 16.67 6.25 5.56 10.00

0.250 20.00 7.69 6.67 11.11

0.333 24.98 10.00 8.33 12.50

0.500 33.33 14.29 11.11 14.29

1.00 50.00 25.00 16.67 16.67

2.00 66.67 40.00 22.22 18.18

2.50 71.40 45.45 23.81 18.52

3.33 76.92 52.63 25.64 18.87

4.00 80.00 57.14 26.67 19.00

5.00 83.33 62.50 27.77 19.23

1. Which of the following are consistent with the laws of thermodynamics?

Energy can not be created or destroyed, but it can be transformed from one form to another
Energy can be created, but a cell must do work in order to accomplish this
Entropy decreases with every energy transformation
Once energy has been used to do work, it is destroyed.

2. Which of the following statements about individual enzymes is NOT true

They are organic compounds, usually made of protein
They are biological catalysts which increase the rates of chemical reactions
Any given enzyme can function at any pH
Enzymes denature if exposed to high temperature

3. Pepsin (an enzyme found in the stomach) acts best at pH of about 2, but is not active at pH 7 because...

It has become denatured
The high pH acts as a non-competitive inhibitor
Feedback inhibition
Substrates break down at pH higher than 5

4. ATP is important in cells because...

It is an inorganic cofactor
It transfers energy released from endergonic reactions to power exergonic reactions
It is an enzyme
It transfers energy released from exergonic reactions to power endergonic reactions

1.You have discovered a novel toxin-encoding gene in a bacterial pathogen. An adjacent gene encodes a putative transcriptional regulator protein. You decide to identify the promoter for the toxin gene and investigate whether the transcriptional regulator protein controls expression from this promoter. Describe your experimental approach to investigate these questions

2a.Describe how the lac repressor protein is involved in controlling expression of the lac operon.

2b.Explain the difference between homologous recombination and site-specific recombination.

3a.Most genome sequencing projects have used an approach known as "shotgun genome sequencing”. Briefly describe how shotgun sequencing works.

3b.DNA transposons and retrotransposons are both types of mobile elements. Describe these two mobile elements and explain how they differ from each other.

4a.For the following restriction enzymes: A) Xmal C|CCGGG (B) Smal CCC|GGG (C) Sdal CCTGCA|GG (D) Pstl CTGCA|G

(i) What is the length and nature (5’ or 3’) of the overhang generated by each restriction enzyme? (ii) Which pair of these enzymes generate sticky ends that are compatible with each other?

4b.The successful construction and transplantation into a cell of a synthetic Mycoplasma genome was an important milestone in synthetic biology. Briefly describe the approach used in this project

5a.What was different between the genome sequencing approaches used by the public human genome project and the private human genome project led by Craig Venter?

5b.What is systems biology? Give two examples of experimental approaches that have been used in systems biology research.

5c.Describe the principles behind and the applications of the following:

a) Reverse transcriptase-PCR b) Cloning DNA into a plasmid vector c) SDS-PAGE d) Restriction mapping e) Sanger Sequencing of DNA

Is the pH at the equivalence point always equal to 7? Explain your answer based on your experimental observations. Include a discussion of equivalence point pH values for strong versus weak acids.

Both Glucose and Fatty Acids can be completely oxidized to CO2, with the energy release used for the synthesis of ATP. In what ways are the biochemical processes involved similar or identical, and how do they diverge?

Describe the two-part reaction carried out by an amino acyl tRNA synthetase. Show the reactants, the products, and the energy source that is used to drive the reaction forward. Show how a tRNA is finally modified by this reaction.

Preventing the construction of amino acid cross-bridges between peptidoglycan chains is the mechanism of action of the _____________________________ antibacterial drugs.

Question 38 options:

n a 800 word essay describe the path followed by an amino acid from absorption to delivery to a cell. Compare this path with the one followed by a large fatty acid. Support your essay with scholarly resources.

4. Draw and label a generic structure of an amino acid

5. Contrast and compare DNA and RNA in at least 3 ways

6. Briefly define negative and positive feedback and give a brief example of each